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Have anybody heard about this method where the microinfusion pump is implanted subcutaneously , for eye drops/drug delivery....since docdors make all kind of complicated operatins, it should not be impossible as well to do in humans,
I have read one article made
on human:
Subcutaneous abdominal artificial tears pump-reservoir for severe dry eye
http://www.ingentaconnect.com/conten...e?format=print
Authors: Murube J.; Murube E.; ChenZhuo L.; Rivas L.
Source: Orbit, Volume 22, Number 1, March 2003 , pp. 29-40(12)
Publisher: Taylor and Francis Ltd
Abstract:
PURPOSE: To assay a totally implanted pump-reservoir unit placed under the subcutaneous tissue of the abdomen for providing artificial tears to the ocular surface in patients with severe dry eye. DESIGN: Prospective non-randomized comparative (self-controlled) trial. PARTICIPANTS: Six patients with severe dry eye, in whom intermittent moistening of the ocular surface with current collyria was clinically unsatisfactory. METHODS: The six patients were treated by implanting an artificial tear pump-reservoir unit under the subcutaneous tissues of the abdomen. The reservoir is operated by a gas pump, which pumps artificial tears to the eye from a 60-ml reservoir through a silicone tube leading subcutaneously from the reservoir, via the chest, neck and lateral part of the head, and entering the conjunctival sac over the lateral canthal ligament. The catheter is anchored to the aponeurosis of the temporal muscle at the lateral rim of the orbit with a butterfly sleeve. The terminal portion of the tube runs freely along the upper conjunctival fornix, and pours 1.5ml/day of the artificial tears into the ocular lacrimal basin with a constant flow rate. The reservoir must be refilled by percutaneous injection of artificial tears every 45 days. MAIN OUTCOME MEASURES: Schirmer test, corneal fluorescein staining, lacrimal film breakup time, lacrimal osmolarity, corneal impression cytology, best-corrected visual acuity, dryness sensation and blepharospasm before and after lacrimal reservoir implantation. RESULTS: The lacrimal subcutaneous abdominal reservoir was well tolerated with little discomfort. A delivery of 1.5ml/day was enough to maintain a comfortable wet eye. After an average follow-up of 15 months the signs and symptoms of dry eye were dramatically improved. Four of the patients had a severe blepharospasm, which disappeared some weeks after the implantation of the lacrimal abdominal reservoir. CONCLUSION: These are the first totally implanted lacrimal reservoirs in human beings. They have proved to be a good solution for severe dry eye. At present, this method is the only one that permits a maintained wet eye surface, and the performance of corneal, conjunctival, limbal and amniotic membrane transplants in total or almost total xerophthalmia. It may also be a good solution for some of the so-called essential blepharospasms, which are frequently triggered by an underlying dry eye.
Document Type: Research article
oN RABBITS:
http://www.mdconsult.com/das/article...9404010360.pdf
Experimental Study of an Automated
System for the Delivery of Eyedrops
using a Microinfusion Pump
Ji Won Kwon, MD, Jung Suk Kim, BS,
Soo Bong Choi, MD, Jin Hak Lee, MD, and
Won Ryang Wee, MD
PURPOSE: To determine the feasibility of using a commercially
available microinfusion pump for the continuous
delivery of eye drops using a rabbit model.
DESIGN: Laboratory investigation.
METHODS: Tear secretion was measured after attaching a
microinfusion pump to the superior fornix of a rabbit.
The pump was set to deliver artificial tears continuously.
A rabbit eye was first chemically burned with 1N NaOH,
the pump was then set to deliver 0.1% fluorometholone
continuously. Results were compared with those obtained
using 0.1% fluorometholone.
RESULTS: Schirmer tests indicated that an average of 22.3
mm in eyes supported by a pump and an average of 10.3
mm in eyes without pump. Moreover, eyes treated with
corticosteroid delivered by pump recovered faster than
those treated with topical corticosteroid.
CONCLUSIONS: The continuous delivery of eye drops by a
microinfusion pump could be applicable to patients with
severe dry eyes or ocular surface diseases. Further study
should be needed. (Am J Ophthalmol 2005;139:
547–549. © 2005 by Elsevier Inc. All rights reserved.)
THE OCULAR SURFACE, WHICH CONSISTS OF THE CORNEA
and conjunctiva, is critical for normal vision. To maintain
the transparency of the cornea, the cornea, conjunctiva,
eyelids, and lacrimal system must all function properly. Many
conditions reduce tear secretion, such as Sjögren’s syndrome,
cicatrical pemphigoid, Stevens-Johnson syndrome, and corneal
burns. Thus, if an automated eye drop delivery system
could supply artificial tears continuously, it could reduce
damage to the ocular surface, and attenuate disease progression.
The authors sought to develop an automated system for
the continuous delivery of eye drops using a commercially
available microinfusion pump (DANA Diabecare, Sooil Co.
Korea, Figure 1).
In this study we used New Zealand white rabbits that
weighed 2.5 to 3.0 kg each. The animals were housed and
treated according to the guidelines issued by the Association
for Research in Vision and Ophthalmology Resolution on the
Use of Animals in Research.
Accepted for publication Aug 23, 2004.
From the Department of Ophthalmology (J.W.K., J.S.K., J.H.L.,
W.R.W), Seoul National University College of Medicine, and Artificial
Eye Center (S.B.C.), Clinical Research Institute, Department of Internal
Medicine, College of Medicine, Konkuk University, Choongju, Korea.
This study was supported by a grant from Korea Research Foundation
(grant KRF-2001-041-F00217).
Inquiries to Dr. Won Ryang Wee, Department of Ophthalmology, College
of Medicine, Seoul National University, 28 Yongon-Dong, Chongno-Gu,
Seoul 110-744, Korea; fax: 82-2-741-3187; e-mail: wrwee@snu.ac.kr
VOL. 139, NO. 3 BRIEF REPORTS 547
Following the induction of general anesthesia by an intramuscular
injection of 2.5 cc/kg ketamine chloride and 0.1
cc/kg xylazine hydrochloride, a silicone tube was connected
to a microinfusion pump inserted subcutaneously from behind
the ear to the outer canthus. The pump was set to administer
eye drops at a rate of 1 l/min and mounted on the back of
the rabbit using a specially designed jacket.
A microinfusion pump was attached to each of 5 rabbits in
this manner and set to deliver artificial tears (Optagent, Samil
Pharmaceutical Co., Korea) to one eye in each rabbit. The
Schirmer test was conducted on both eyes of the 5 rabbits
over a 5-day period. Schirmer test strips (Cooper Vision
Pharmaceuticals Inc. USA) were inserted into the outer 1/3
of the inferior fornix for 5 minutes, and the amount of
moisture was measured in millimeters.1 Eyes connected to
pumps received an average of 22.3 mm/5 minutes/eye whereas
eyes not connected to pumps received 10.3 mm/5 minutes.
To measure the effect of the continous delivery of corticosteroid
eye-drops after an alkali burn, we administered an
alkali burn in one eye of 10 rabbits. Corneal centers were
burned to a diameter 10 mm using filter paper soaked in 1N
NaOH solution for 60 seconds, and then washed with 20cc of
Balanced Salt Solution (BSS, Alcon, USA). Microinfusion
pumps were then attached to 5 alkali burnt eyes and set to
deliver 0.1% fluorometholone (Flumetholone, Taejoon
Pharm Co. Ltd) at a rate of 1 l/min. The other 5 alkali burnt
eyes were treated with 0.1% fluorometholone 4 times daily as
control. Impression cytology was conducted on the conjunctiva
of all 10 eyes on the first, third, fifth, eighth, and 10th
days postburn administration. Samples were observed by light
microscopy. For comparison purposes with normal eyes,
impression cytology was conducted using the same methods
FIGURE 2. Corneal photograph at 7 days after operation
without pump (upper) and with pump (lower). Cornea treated
with pump supplied corticosteroid eyedrops showed better
recovery after alkali burn administration.
FIGURE 1. Microinfusion pump (DANA Diabecare, Sooil, Korea).
548 AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2005
on healthy rabbit eyes. The eyes fitted with pumps showed
faster recovery rates with respect to turbidity (Figure 2), and
impression cytology also showed better conjunctival epithelium
recovery in the eyes connected to pumps.
Several efforts have been made to develop continuous
drug delivery systems.2–5
The microinfusion pump used in the present study was
originally developed for insulin treatment in diabetics and
was designed to deliver a proper dosage at a constant rate.
The reported supply rate of normal tears is 0.6 to 1.2
l/min, and thus the pump delivery flow rate was set at 1
l/min. The subjects of the present study were rabbit eyes.
Before application to people, a suitable pump and improved
surgical procedures must be developed to reduce the inconvenience
of carrying a pump and the discomfort of the
surgical installation.
REFERENCES
1. Abrams KL, Brooks DE, Funk RS, Theran P. Evaluation of the
Schirmer tear test in clinically normal rabbits. Am J Vet Res
1990;51:1912–1913.
2. Friedberg ML, Pleyer U, Mondino BJ. Device drug delivery to
the eye, Collagen shields, iontophoresis, and pumps. Ophthalmology
1991;98:725–732.
3. Dohlman CH, Doane MG, Reshmi CS. Mobile infusion
pumps for continuous delivery of fluid and therapeutic agents
to the eye. Ann Ophthalmol 1971;3:126 –128.
4. Karesh JW, Nirankari VS. An improved method for the
delivery of artificial tears using an infusion pump. Invest
Ophthalmol Vis Sci 1986;27:1284 –1288.
5. Rehkopf PG, Mondino BJ, Brown SI, Goldberg DB. A
long-term implantable aqueous delivery system for the external
rabbit eye. Invest Ophthalmol Vis Sci 1980;19:428–430.
AND ONE ON DOGS....
I have read one article made
on human:
Subcutaneous abdominal artificial tears pump-reservoir for severe dry eye
http://www.ingentaconnect.com/conten...e?format=print
Authors: Murube J.; Murube E.; ChenZhuo L.; Rivas L.
Source: Orbit, Volume 22, Number 1, March 2003 , pp. 29-40(12)
Publisher: Taylor and Francis Ltd
Abstract:
PURPOSE: To assay a totally implanted pump-reservoir unit placed under the subcutaneous tissue of the abdomen for providing artificial tears to the ocular surface in patients with severe dry eye. DESIGN: Prospective non-randomized comparative (self-controlled) trial. PARTICIPANTS: Six patients with severe dry eye, in whom intermittent moistening of the ocular surface with current collyria was clinically unsatisfactory. METHODS: The six patients were treated by implanting an artificial tear pump-reservoir unit under the subcutaneous tissues of the abdomen. The reservoir is operated by a gas pump, which pumps artificial tears to the eye from a 60-ml reservoir through a silicone tube leading subcutaneously from the reservoir, via the chest, neck and lateral part of the head, and entering the conjunctival sac over the lateral canthal ligament. The catheter is anchored to the aponeurosis of the temporal muscle at the lateral rim of the orbit with a butterfly sleeve. The terminal portion of the tube runs freely along the upper conjunctival fornix, and pours 1.5ml/day of the artificial tears into the ocular lacrimal basin with a constant flow rate. The reservoir must be refilled by percutaneous injection of artificial tears every 45 days. MAIN OUTCOME MEASURES: Schirmer test, corneal fluorescein staining, lacrimal film breakup time, lacrimal osmolarity, corneal impression cytology, best-corrected visual acuity, dryness sensation and blepharospasm before and after lacrimal reservoir implantation. RESULTS: The lacrimal subcutaneous abdominal reservoir was well tolerated with little discomfort. A delivery of 1.5ml/day was enough to maintain a comfortable wet eye. After an average follow-up of 15 months the signs and symptoms of dry eye were dramatically improved. Four of the patients had a severe blepharospasm, which disappeared some weeks after the implantation of the lacrimal abdominal reservoir. CONCLUSION: These are the first totally implanted lacrimal reservoirs in human beings. They have proved to be a good solution for severe dry eye. At present, this method is the only one that permits a maintained wet eye surface, and the performance of corneal, conjunctival, limbal and amniotic membrane transplants in total or almost total xerophthalmia. It may also be a good solution for some of the so-called essential blepharospasms, which are frequently triggered by an underlying dry eye.
Document Type: Research article
oN RABBITS:
http://www.mdconsult.com/das/article...9404010360.pdf
Experimental Study of an Automated
System for the Delivery of Eyedrops
using a Microinfusion Pump
Ji Won Kwon, MD, Jung Suk Kim, BS,
Soo Bong Choi, MD, Jin Hak Lee, MD, and
Won Ryang Wee, MD
PURPOSE: To determine the feasibility of using a commercially
available microinfusion pump for the continuous
delivery of eye drops using a rabbit model.
DESIGN: Laboratory investigation.
METHODS: Tear secretion was measured after attaching a
microinfusion pump to the superior fornix of a rabbit.
The pump was set to deliver artificial tears continuously.
A rabbit eye was first chemically burned with 1N NaOH,
the pump was then set to deliver 0.1% fluorometholone
continuously. Results were compared with those obtained
using 0.1% fluorometholone.
RESULTS: Schirmer tests indicated that an average of 22.3
mm in eyes supported by a pump and an average of 10.3
mm in eyes without pump. Moreover, eyes treated with
corticosteroid delivered by pump recovered faster than
those treated with topical corticosteroid.
CONCLUSIONS: The continuous delivery of eye drops by a
microinfusion pump could be applicable to patients with
severe dry eyes or ocular surface diseases. Further study
should be needed. (Am J Ophthalmol 2005;139:
547–549. © 2005 by Elsevier Inc. All rights reserved.)
THE OCULAR SURFACE, WHICH CONSISTS OF THE CORNEA
and conjunctiva, is critical for normal vision. To maintain
the transparency of the cornea, the cornea, conjunctiva,
eyelids, and lacrimal system must all function properly. Many
conditions reduce tear secretion, such as Sjögren’s syndrome,
cicatrical pemphigoid, Stevens-Johnson syndrome, and corneal
burns. Thus, if an automated eye drop delivery system
could supply artificial tears continuously, it could reduce
damage to the ocular surface, and attenuate disease progression.
The authors sought to develop an automated system for
the continuous delivery of eye drops using a commercially
available microinfusion pump (DANA Diabecare, Sooil Co.
Korea, Figure 1).
In this study we used New Zealand white rabbits that
weighed 2.5 to 3.0 kg each. The animals were housed and
treated according to the guidelines issued by the Association
for Research in Vision and Ophthalmology Resolution on the
Use of Animals in Research.
Accepted for publication Aug 23, 2004.
From the Department of Ophthalmology (J.W.K., J.S.K., J.H.L.,
W.R.W), Seoul National University College of Medicine, and Artificial
Eye Center (S.B.C.), Clinical Research Institute, Department of Internal
Medicine, College of Medicine, Konkuk University, Choongju, Korea.
This study was supported by a grant from Korea Research Foundation
(grant KRF-2001-041-F00217).
Inquiries to Dr. Won Ryang Wee, Department of Ophthalmology, College
of Medicine, Seoul National University, 28 Yongon-Dong, Chongno-Gu,
Seoul 110-744, Korea; fax: 82-2-741-3187; e-mail: wrwee@snu.ac.kr
VOL. 139, NO. 3 BRIEF REPORTS 547
Following the induction of general anesthesia by an intramuscular
injection of 2.5 cc/kg ketamine chloride and 0.1
cc/kg xylazine hydrochloride, a silicone tube was connected
to a microinfusion pump inserted subcutaneously from behind
the ear to the outer canthus. The pump was set to administer
eye drops at a rate of 1 l/min and mounted on the back of
the rabbit using a specially designed jacket.
A microinfusion pump was attached to each of 5 rabbits in
this manner and set to deliver artificial tears (Optagent, Samil
Pharmaceutical Co., Korea) to one eye in each rabbit. The
Schirmer test was conducted on both eyes of the 5 rabbits
over a 5-day period. Schirmer test strips (Cooper Vision
Pharmaceuticals Inc. USA) were inserted into the outer 1/3
of the inferior fornix for 5 minutes, and the amount of
moisture was measured in millimeters.1 Eyes connected to
pumps received an average of 22.3 mm/5 minutes/eye whereas
eyes not connected to pumps received 10.3 mm/5 minutes.
To measure the effect of the continous delivery of corticosteroid
eye-drops after an alkali burn, we administered an
alkali burn in one eye of 10 rabbits. Corneal centers were
burned to a diameter 10 mm using filter paper soaked in 1N
NaOH solution for 60 seconds, and then washed with 20cc of
Balanced Salt Solution (BSS, Alcon, USA). Microinfusion
pumps were then attached to 5 alkali burnt eyes and set to
deliver 0.1% fluorometholone (Flumetholone, Taejoon
Pharm Co. Ltd) at a rate of 1 l/min. The other 5 alkali burnt
eyes were treated with 0.1% fluorometholone 4 times daily as
control. Impression cytology was conducted on the conjunctiva
of all 10 eyes on the first, third, fifth, eighth, and 10th
days postburn administration. Samples were observed by light
microscopy. For comparison purposes with normal eyes,
impression cytology was conducted using the same methods
FIGURE 2. Corneal photograph at 7 days after operation
without pump (upper) and with pump (lower). Cornea treated
with pump supplied corticosteroid eyedrops showed better
recovery after alkali burn administration.
FIGURE 1. Microinfusion pump (DANA Diabecare, Sooil, Korea).
548 AMERICAN JOURNAL OF OPHTHALMOLOGY MARCH 2005
on healthy rabbit eyes. The eyes fitted with pumps showed
faster recovery rates with respect to turbidity (Figure 2), and
impression cytology also showed better conjunctival epithelium
recovery in the eyes connected to pumps.
Several efforts have been made to develop continuous
drug delivery systems.2–5
The microinfusion pump used in the present study was
originally developed for insulin treatment in diabetics and
was designed to deliver a proper dosage at a constant rate.
The reported supply rate of normal tears is 0.6 to 1.2
l/min, and thus the pump delivery flow rate was set at 1
l/min. The subjects of the present study were rabbit eyes.
Before application to people, a suitable pump and improved
surgical procedures must be developed to reduce the inconvenience
of carrying a pump and the discomfort of the
surgical installation.
REFERENCES
1. Abrams KL, Brooks DE, Funk RS, Theran P. Evaluation of the
Schirmer tear test in clinically normal rabbits. Am J Vet Res
1990;51:1912–1913.
2. Friedberg ML, Pleyer U, Mondino BJ. Device drug delivery to
the eye, Collagen shields, iontophoresis, and pumps. Ophthalmology
1991;98:725–732.
3. Dohlman CH, Doane MG, Reshmi CS. Mobile infusion
pumps for continuous delivery of fluid and therapeutic agents
to the eye. Ann Ophthalmol 1971;3:126 –128.
4. Karesh JW, Nirankari VS. An improved method for the
delivery of artificial tears using an infusion pump. Invest
Ophthalmol Vis Sci 1986;27:1284 –1288.
5. Rehkopf PG, Mondino BJ, Brown SI, Goldberg DB. A
long-term implantable aqueous delivery system for the external
rabbit eye. Invest Ophthalmol Vis Sci 1980;19:428–430.
AND ONE ON DOGS....
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